Trump's comments slightly softened his earlier tweets on April 8 where he directly blamed Russia, Syria and Iran for the alleged chemical attack.

Later in the evening, he held a meeting on Syria with his top military and national security officials.

The reported death toll in Douma ranges from between 40-80 people, including many young children.

Hawkish Republican Senator John McCain has warned U.S. PresidentDonald Trump against pulling American forces from Syria, saying the president's recent announcement appears to have "emboldened" Syrian President Bashar Assad.

The guided missile destroyer is armed with Tomahawk cruise missiles, the weapon of choice in a United States attack one year ago on an airfield in Syria following an alleged sarin gas attack on civilians. Washington denied this, and France, which in February had said it would strike in the event of a chemical weapons attack on civilians by Syrian government forces, also said its forces were not involved.

Syrian state media and Russian Foreign Ministry did not take responsibility for Saturday's attacks in Douma.

Trump on Tuesday cancelled plans to travel to South America later this week, choosing to stay in the United States to manage the response to the events in Syria.

Earlier, the United Nations human rights chief said world powers were treating chemical weapons use with a "collective shrug".

The punitive raid did not draw U.S. forces any deeper into Syria's civil war, nor did it dissuade Syria or its Russian and Iranian backers from pursuing their campaign against rebel groups.

US Ambassador to the UN Nikki Haley stated, "I could hold up pictures of babies lying dead next to their mothers, in their diapers, all lying together, dead, ashen blue, open eyed and lifeless, white foam bubbling from their mouths and noses" concerning the so-called chemical attack.

Israel fears Iran could use Syria's territory to stage attacks on it.

"We are at the edge of a risky precipice", the diplomat said.

"We have reached the moment when the world must see justice done", Ms Haley told the Council. History will record this as the moment when the Security Council either discharged its duty or demonstrated its utter and complete failure to protect the people of Syria.

President Donald Trump said Monday he will make a decision as early as this evening on the USA response to what he called an "atrocious" chemical weapons attack on civilians in Syria and warned that he will hold the responsible parties accountable.

Trump said the administration will make a decision within the next 24 to 48 hours, according to a White House press pool report.

Fielding questions at the White House, Trump press secretary Sarah Sanders said it would be "outrageous" to say that Trump's recent announcement that he intends to remove all USA forces from Syria in the coming months had emboldened Assad.